Stacking and cascading difference
Cascade is connected to other hubs through a port of the hub, such as using a hub UPLINK port to another normal port; and stacking is connected by the backplane of the hub, it is a kind of built on the chip level. Connection, such as 2 24-port switches are like a 48-port switch, and the advantage is that there is no problem of bottlenecks.
Stacking and cascading (UPLINK) are two ways to connect together multiple switches or hubs. Their main purpose is to increase port density. But their implementation is different. Simply put, cascading can be completed between the hubs between any network device manufacturers through a twisted pair, or between the hubs, or between the switches. The stack is only between the equipment of its own manufacturers, and this device must have a stack function. Cascades only need to do a twisted pair (or other medium), stack the need for a dedicated stacking module and stack cable, and these devices may need to purchase separately. The cascade of the switch is theoretically without a level limit (note: the intersector level has a number of limitations, and the requirements of 10m and 100m are different), and the equipment that stacks the various manufacturers will indicate the maximum number of stacks.
From the above, it can be seen that the cascading is relatively easy, but stacking this technological level unacceptable advantage. First, multiple switches are stacked together, logically, they belong to the same device. This way, if you want to set these switches, you can see other switches in the stack as long as you connect to any device. The cascade device is logically independent, and if you want the network management, you must be connected to each device.
Second, multiple equipment-level linkage will result in a stage bottleneck. For example, two 100M switches are connected by a twisted pair, and their cascading bandwidth is 100 megadownload. Such a computer between different switches should be communicated, they can only pass this 100 megabytes. The two switches are connected together by stacking, the stacked cable will provide a backplane bandwidth higher than 1G, greatly reduced the bottleneck. Now there is a new technology -port trunking that can be used in two switches in two switches in this technique. This can be used to increase the stage bandwidth.
The cascading is still a stacked purpose, which is to increase connection distance. For example, a computer is far away from the switch, which exceeds the maximum distance of the single twisted pair, and a switch can be placed in the middle to connect the computer to this switch. The longest stacked cable is only a few meters, so it should be considered when stacking. The stack and cascading have the advantages that often appear simultaneously in the actual programming design.
Cascading is connected to other hubs through a port of the hub, while the stack is connected by the backplane of the hub. Although the cascading and stacks can achieve an expansion of the number of ports, the cascading, each hub or switch is logically still a network management device, while the stacked several hubs or switches are logically a network management device of.
